[Bug]: Socks5 Proxy - Could not find server (seems to not use DNS over Proxy anymore)

### ⚠️ Before submitting, please verify the following: ⚠️

- [x] This is a **bug**, not a question or a configuration issue.
- [x] This issue is **not** already reported on Github (I've searched it).
- [x] Nextcloud Server and Desktop Client are **up to date**. See [Server Maintenance and Release Schedule](https://github.com/nextcloud/server/wiki/Maintenance-and-Release-Schedule) and [Desktop Releases](https://nextcloud.com/install/#install-clients) for supported versions.
- [x] I agree to follow Nextcloud's [Code of Conduct](https://nextcloud.com/contribute/code-of-conduct/)

### Bug description

Updated to 3.14.1 and 3.14.2 now and the did not work anymore over my local socks5 proxy. DNS must be done over the proxy, so i seems this is the culprit,as the error in the gui is "host not found".

The proxy works for all, also for nextcloud in the browser.
...

### Steps to reproduce

1.Configure Socks5 proxy
2.Try to use

Source is from the ppa:
https://ppa.launchpadcontent.net/nextcloud-devs/client/ubuntu noble main

### Expected behavior

host found and sync works again
...

### Which files are affected by this bug

connection no files

### Operating system

Linux

### Which version of the operating system you are running.

Linux Mint 22 wilma

### Package

Other

### Nextcloud Server version

30.0.1

### Nextcloud Desktop Client version

3.14.2

### Is this bug present after an update or on a fresh install?

Updated from a minor version (ex. 3.4.2 to 3.4.4)

### Are you using the Nextcloud Server Encryption module?

Encryption is Disabled

### Are you using an external user-backend?

- [x] Default internal user-backend
- [ ] LDAP/ Active Directory
- [ ] SSO - SAML
- [ ] Other

### Nextcloud Server logs

_No response_

### Additional info

client logs

(i) server host changed to cloud.nextcloud.tld in the logs for privacy (hope thats ok)

[...]
2024-10-23 14:56:39:392 [ warning qt.core.qobject.connect unknown:0 ]: QObject::connect(QNetworkInformation, OCC::Application): invalid nullptr parameter
2024-10-23 14:56:39:482 [ warning qt.qml.context unknown:0 ]: qrc:/qml/src/gui/tray/MainWindow.qml:313:29 Parameter "index" is not declared. Injection of parameters into signal handlers is deprecated. Use JavaScript functions with formal parameters instead.
[...]
2024-10-23 14:56:39:590 [ warning nextcloud.sync.networkjob ./src/libsync/abstractnetworkjob.cpp:223 ]: QNetworkReply::HostNotFoundError "Host cloud.nextcloud.tld konnte nicht gefunden werden" QVariant(Invalid)
2024-10-23 14:56:39:590 [ warning nextcloud.sync.credentials.webflow ./src/gui/creds/webflowcredentials.cpp:207 ]: QNetworkReply::HostNotFoundError
2024-10-23 14:56:39:590 [ warning nextcloud.sync.credentials.webflow ./src/gui/creds/webflowcredentials.cpp:208 ]: "Host cloud.nextcloud.tld konnte nicht gefunden werden"
2024-10-23 14:56:39:590 [ warning nextcloud.sync.networkjob.checkserver ./src/libsync/networkjobs.cpp:546 ]: error: status.php replied 0 ""
2024-10-23 14:56:39:590 [ warning nextcloud.sync.connectionvalidator ./src/gui/connectionvalidator.cpp:160 ]: QNetworkReply::HostNotFoundError "Host cloud.nextcloud.tld konnte nicht gefunden werden" "Host cloud.nextcloud.tld konnte nicht gefunden werden" ""
2024-10-23 14:56:39:590 [ warning nextcloud.sync.credentials.webflow ./src/gui/creds/webflowcredentials.cpp:207 ]: QNetworkReply::HostNotFoundError
2024-10-23 14:56:39:590 [ warning nextcloud.sync.credentials.webflow ./src/gui/creds/webflowcredentials.cpp:208 ]: "Host cloud.nextcloud.tld konnte nicht gefunden werden"
2024-10-23 14:56:39:590 [ info nextcloud.gui.account.state ./src/gui/accountstate.cpp:368 ]: AccountState connection status change: OCC::ConnectionValidator::Undefined -> OCC::ConnectionValidator::StatusNotFound
[...]

Reproduce the SOCKS5 failure on Linux Mint with Nextcloud Desktop 3.14.2, then trace the HostNotFoundError through src/libsync/abstractnetworkjob.cpp, src/libsync/networkjobs.cpp, src/gui/connectionvalidator.cpp, and src/gui/creds/webflowcredentials.cpp. Check how DNS resolution behaves through the proxy; done means the host is found and synchronization works again.

Written by the indexing model from the issue text.